cmd/go: drop -v from go help get

Fixes #37301

Change-Id: I6d6ac818a73b907638f62d56bd5a7f00a6e6a5ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/632178
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

src/cmd/go/internal/modget/get.go

@@ -54,7 +54,7 @@ import (
 var CmdGet = &base.Command{
 	// Note: flags below are listed explicitly because they're the most common.
 	// Do not send CLs removing them because they're covered by [get flags].
-	UsageLine: "go get [-t] [-u] [-v] [-tool] [build flags] [packages]",
+	UsageLine: "go get [-t] [-u] [-tool] [build flags] [packages]",
 	Short:     "add dependencies to current module and install them",
 	Long: `
 Get resolves its command-line arguments to packages at specific module versions,
@@ -222,7 +222,6 @@ var (
 	getU        upgradeFlag
 	getTool     = CmdGet.Flag.Bool("tool", false, "")
 	getInsecure = CmdGet.Flag.Bool("insecure", false, "")
-	// -v is cfg.BuildV
 )
 
 // upgradeFlag is a custom flag.Value for -u.